In Malory, Tristan has a brief affair with Segwarides' wife, and
wounds the knight after being found out. Tristan encounters
Segwarides later on the Isle of Servage. Segwardies forgives the
more famous knight saying he "will never hate a noble knight for a
light lady", and the two team up to avoid the dangers of the isle.
Soon afterwards Tristan makes Segwarides Lord of Servage.

Sir Segwarides is killed trying to repel Sir Launcelot's rescue
of Guinevere from the
stake.